Originally Posted by jbander
I think I may be misunderstanding something and would like it cleared up for me. I want a fuel pressure shutoff switch to protect against potential problems with the nitrous. So I've heard that you can use a oil pressure safety switch as a shutoff for the electric fuel pump when running Nitrous . Now I assumed that meant that it was installed in the oil system but now I wonder if that is wrong and should be installed instead in the fuel system. The simple solution is simply run fuel pressure switch that is dedicated as a fuel pressure switch which I will be doing . But I'm still intrigued with the answer about using the oil pressure switch as the safety shutoff for nitrous, One more question if I may. What pressure is used for fuel pressure switch for nitrous. Thank You
They are talking about using a cheaper to purchase oil pressure switch to sense fuel pressure. the switch is pressure on style which is backwards from an oil pressure idiot light switch and more like a brake light switch that is in the 'on' position with pressure.
This is placed in the relay ground circuit such that loss of fuel oressure results in the switch opening thus breaking the circuit and shutting off the pump.
NOx stores sell a pressure switch for this they run around 50 dollars which is about 4 times the price of an oil pressure switch.
The problem with using an oil or brake pressure switch in this function is not knowing it the internals are rated to keep gasoline (a mixture of high energy solvents) from eating up the insides and leaking through the pressure seal. At fuel system pressures even a small ooze of fuel is a big time fire risk.